1. Field of the Invention
The disclosed embodiments of the present invention relate to optical sensing, and more particularly, to a non-contact optical sensing apparatus, which uses a triangulation technique to obtain position information of an object, and a related non-contact optical sensing method.
2. Description of the Prior Art
With the advent of personal electronic products (e.g. a mobile phone or a personal computer (PC)), many control methods for human-device interaction have been popular. For example, an electronic mouse enables a user to trace a position on a screen and give instruction such as menu selection or editing contents on the screen. Regarding touch-screen sensor technologies (including capacitive, resistive, magnetic or surface acoustic wave types), the user can directly point to a position on the screen and move object (s) across the screen. In addition, some sensing devices (e.g. an air mouse or a three-dimensional (3D) mouse) allow the user to move them in the air to trace a position on the screen.
However, as none of the above control methods allows a bare hand or finger(s) to trace a screen position in a distance from the screen (i.e. without touching the screen), it is inconvenient for the user to trace a position on the screen in some circumstances. For example, when a user's hand is dirty from performing mechanic works, or greasy from handling the food, the user will prefer a non-contact method to track a screen position without touching the screen. In some other use case where the screen may be held in a distance away from the user, a contact touch method is not suitable for screen position tracking.
Thus, there is a need for a novel non-contact sensing mechanism to facilitate human-machine interaction.